The occurrence of post-operative vertigo after cochlear implantation

Background. The incidence of postoperative vertigo after cochlear implantation (CI) varies a lot in the literature. The aim of this work was to investigate both subjective complaints of vertigo before and after cochlear implantation and related it to to the preoperative vestibular function, the surgical procedure and to the position of CI at the postoperative neuroradiological study. Methods. Retrospective cohort study of adult CI series operated by the same surgeon (DZ) over the last 3 years. (N= 107). Sixty-six subjects (38 F; 28 M), aged from 21 to 78 years old were included in the study, lasting 83 CI. The outcomes of the pre-operative vestibular assessment were extracted from the database of the Vestibular Disorders Unit of the tertiary referral University Hospital of Milano from 1992 to 2018 (N=557). Post-operative presence/absence of vestibular disorders was analyzed and related to the preoperative vestibular examination and to the flat-panel computed tomography (FPCT) findings. Results: The patients were divided by age and by the presence of vestibular response of the operated ear measured by videoculography, caloric testing and video-impulse test. Sensorial analysis by static posturography was also included. The incidence of postoperative vertigo was higher in patients > 65 years old (36.3% vs 20.4%, p=0.03). Postoperative vertigo did not result related to the surgical procedure. The results are discussed with the review of the literature. Conclusion: Our results confirm the importance of vestibular testing in CI recipients, in order to better counsel the patient on the foreseeable post-operative course and to identify those patients who will need a vestibular rehabilitation.